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Heat transfer by mobile low-frequency phonons and "localized" modes in cryocrystal solutions

V. A. Konstantinov·E. S. Orel·V. P. Revyakin
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Abstract

The temperature and volume dependences of the thermal conductivity of solid Kr(1-x)Xe(x)solution are analyzed within the model in which heat is transferred by mobile low-frequency phonons; above the phonon mobility edge this is done by "localized" modes migrating randomly from site to site. The phonon mobility edge (w0)is determined from the condition that the phonon mean -free path restricted by Umklapp processes and point defects scattering cannot be smaller than one-half the phonon wavelength. The Bridgman coefficient is the weighted - mean over these modes whose volume dependences differ widely. It is shown that the amount of heat transferred by the "localized" modes above 100 K is quite large even in pure Kr and it increases with rising temperature and impurity concentration.

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V. A. Konstantinov, E. S. Orel, V. P. Revyakin. 2003-01-02. Heat transfer by mobile low-frequency phonons and "localized" modes in cryocrystal solutions. https://arxiv.org/abs/cond-mat/0301011

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